Yo,
since a lot of my backhand resolves around my wrist, I bought a powerball to exercise. I think that it can actually help, my problem is that I kinda get "addicted" to it.
What I mean is that if I don't have the ball in my hand I feel my arm doing the movement on his own or having the feeling of the ball in my hand even though it is not. It worries me if this can have any long term effects especially when playing table tennis. Does anybody have more experience with it?